怎么把网页状态栏上滚动的文字速度调慢

<script language="JavaScript">

 var msg  = "文字 " ;

var interval = 120

var spacelen = 120;

var  space20=" ";

var seq=0;

var speed = 1;

var speed = 2;

function Scroll() {

len = msg.length;

window.status = msg.substring(0, seq+1);

seq++;

if ( seq >= len ) {

seq = 0;

window.status = '';

window.setTimeout("Scroll();", interval );

}

else

window.setTimeout("Scroll();", interval );

}

Scroll();

</script>

怎么把滚动字的速度调慢一些

interval = 120

是控制速度的，把数字调大就慢了